Lapping-head.



\ A. & 1. c. SAFKAQI" LAPPING HEAD.

APPLICATION man JULY 20.1918.

Patented Nov. 12, 1918.

link 7/4! InvenTars. Alfred Scxfka g dose oh L'IAS'cUkc: 5! W [May Wifness.

'uirnn STATES PATENT orFIoE.

Elz'iFZi'A AND JOSEPH G. SAFKA, OF PHILADELPHIA, PENNSYL ANIA.

LAPPING-HEAD.

To all whom. if may concern."

' lie it known that we. ALF-nun Serum and losers Cnwums SAFKA, citizens of the United States, residing at 5731 Cedar -Ave. and'fZSlQO Poplar St. rcspectiiely, Philadelphis in the countypf l hiludelphia and State of Pennsylvania, have invented new and useful improvements in Lapping-Heads, of which the following is a specification.

This invention relates to certain new and useful improvements in lapping heads. such as are usually employed for finishing the bores of guns, cylinders and the like.

The main. object of our invention is to provide a positive. tool of the type referred to which can he used at. very high speed, whereby a great saving oi to .ie is effected.

A further object of our invention is to provide a simple, eihcient and durable lap ping tool which comprehends certain novel features whereby better results are obtained, and which by the nature of its construction is rendered portable, and further, it can be employed in any desired position.

lVith these and other objects in view. this invention consists in the details of construction and combination of parts hereinafter set foith and then specifically pointed out by thcappended claims. In order that those skilled in the art to which this invci'ition appertains may understand how to make and use the same the construction and operation will now he des..ribed in detail, reference being had to the accompanying drawing, forming a part of this specification, and in which Figure l is a combined horizontal longitudinal section and elevation of the lappin head. i i

2 is an end elevation of the lapping; head with the end pieces removed.

Fig. 3 is a plan view of the lapping head as seen when assembled.

Fig. 1- is an end elevation of seen when asseinhle; 1v

5 is a section of the end pieces or disks showingthe construction of the spring operating and releasingmechanism.

Fig. ('3 is a sectional elevation showing the construction of collapsing; mechanism. and v Fig. 7 is a perspective view of the clamp for holding the sheet or sheets of abrasive material taut about laps.

Referring. to the drawings the letter A represents a hollow shaft upon which the Specification of Letters Patent.

the guides and spring Patented Nov. 12, 1918.

Application filed July 20, 1918. erial No. 245.895.

lapping head is fastened, and which is the medium by which the power to operate the lapping head is transmitted. B and B are the lap plates upon which the sheets containing the abrasive material are placed, and to which these sheets are clamped by means of the clamping bars C which are secured to the laps B and B by pins C and clamped tight on the sheets by wing nuts C threaded on studs prevented from moving laterally and trans versely to any great extent by guide pins B which are screwed into and fastened rigidly to the lap plates. The lap plates are further prevented from moving laterally and transversely by pins P, which are also screwed into and fastened rigidly to the lap plates, and which also serve as guides. The principal use. however, of the pin B is to operate in conjunction with'the springs E", wl ich are held in place by nuts The parts B B, i and B operate in spiders D and D which are keyed by a key D and securely bolted to the hollow shaft A. The

spiders D and D thus comprise two parts having; three vertical arms each. E and E are disks which bear against the ends of the lap plates B and B thus forcing the lap plates B and B with the sheets containing abrasive material against the surface of the work to be finished or lapped. These disks l5 and E are controlled by the springs Ff interposed between the collars F tllldRShOlllders formed in the disks. The collars F are secured to the hollow The disks E and EQare thus free to move longitudinally over the hollow 'slia-ft A and collars F. The shaft G is'a releasing shaft operating within the hollow shaft A. The operation of the lapping head is as follows: Referring to Fig. 1 the disk E drawn longitudinally along the hollow shaft A and sliding over the collar F, which operation compresses the spring E and draws along with it the solid or releasing shaft (l, which operates Within the hollow shaft. A, and by means of pin H the pin J is drawn through the inclined slots in disk E, thereby imparting a slight rotating motion to the disk E and in this manner pushingit away from the ends of the lap-plates B and B, thus both disks E4and E are free from the lap plates. This allows the springs B to expand against the nuts B which are secured to the pins B and in this manner drawing or collapsing the lap plates The lap plates B and B are shaft A by pins F3 plates H and B. This operation also causes the springs 13 to extend along the pins B the machine is iiiten'dedi interposed between the nuts B and theshouldered-in arms of the spiders D and llhis mechanism is intended to artly eq lize the centrifugal force when t ie en tire lapping head is rotating and partly as, a guide and steadicr---operating Within the arms of spiders D and D'-for the laps B and B, but mainly as a collz tpsing mechan'ism to cause lap plates B and B" to collapse toward hollow shaft A, when inserting the entire lapping head into or IJIIOVlHg' it from the work being finished or lapped. The guide pins B? are the main. guiding and steadyihg pins, also operating Within the v arms of spiders 2D and 11'.

shaft A is then caused to rotate and this sin; turn-rotates the'entire lappinghead as a unit thusperforming the work for whieh Releasing the machine from the .Work is accomplished by the same operation as When-inserting the machine into the WO'l'iL While We have fully described our practical embodiment of our invention we Wish it to be clearly understood, that We do not limit oursel 3:. to the exact construction shown, as sl g t modifications can be made Without departing from the spirit and scope of our invention.

We claim:

l. A lapping h 1 comprising a hollow shaft, springdontrolled lapping ,Iniill'llfilii 'moimteil on 1" *cllow shaft, spring-in l'inented dish me lapted to cooperate with said lapp' nhcrs and force them outwardly lay centr force, and means for separating the and disks to contract the lapping members.

2. A lapping head comprising a hollow shaft, arcuate lapping members mounted on said, shaft, contractile springs acting upon 'sanl lapping members, spring-influenced disk members adapted for coiiperation with T he hollowthe ends of said'lapping members and. normally tending to expand the same and means for moving one of said disks longitudinally and the other spirally of said pollow-shaft to contract the lapping mem iers. 3. A lapping head 'eo m'p'rising'a hollow shaft; arcaate la ping members mounted on said, hollow sha .t, contractile springs operating upon said lappingimembers, springinflueneed disk members adapted for cooperation with the ends of saidlapping members and tending to expand the same, means for moving one of said disks longitudinally and the other spirally of said hollow shaft to contract the lapping members, and means for holding the abrading material on the lapping members.

Q. A lapping head comprising a hollow shaft, arouate' spring actuated lapping members mounted on said hollow shaft, spring-influenced disk members cooperating with the -ends of said lapping members to expandthe same, an inner shaft having" op erative connection with the disk members whereby one of said, disk men'ibers may be moved longitudinally and the other s 'iirally of said hollow shaft to contract the lapping lon 'itadinallv and the other s irall of said hollowshaft, and clamping bars for holding the sheets of abrading material on the. hipping members.

In testimony wher'eo'fwe affix: our signaltnres.

ALFRED SAFKA. JOSEPH O. SAFKA, 

